Pfizer (PFE -0.59%) has been around for over 175 years, but it became a true household name during the COVID-19 pandemic as one of the main vaccine suppliers. That led to its stock price and revenue skyrocketing, and even brought Pfizer's market cap to over $340 billion at one point.

Since its late-2021 peak, Pfizer's stock is down over 60%. In the past three years, it's off by 52%, even while beating its earnings per share (EPS) estimates in all 12 reported earnings in that time.

Pfizer will report its fiscal second-quarter earnings on Aug. 5. Although we won't know if it'll continue its beats streak until then, it's probably not a good idea to try to time your investment around the date. Let's take a look at why.

There's no correlation between Pfizer's earnings and immediate stock price moves

You would think that a company beating its earnings estimates would excite investors and lead to positive stock price movements, but that's unfortunately not how the stock market operates. Other factors influence stock price movements -- such as future guidance, the macroeconomic environment, and overall investor sentiment -- so focusing on earnings alone can misguide you.

Image source: The Motley Fool.

Even with Pfizer's consistency in beating earnings estimates, history has shown that this hasn't always sent its stock price up. The table below shows its next-day stock price movements after earnings reporting.

Data sources: AlphaQuery and YCharts.

Regardless of the company, it's helpful to remember this: It's never a good idea to try to time the market, because the market doesn't behave rationally -- at least, in the short term.

Pfizer is a good value opportunity

If you're looking for reasons to invest in Pfizer, they shouldn't revolve around its upcoming earnings date. Instead, invest because of its cheap valuation and ultra-high dividend yield.

Pfizer is currently trading at 8 times its forward earnings, which is less than competitors like Johnson & Johnson, AbbVie, and Eli Lilly, and far below the S&P 500 healthcare sector's 16.5 average.

PFE PE Ratio (Forward) data by YCharts.

Pfizer's stock has lagged behind the overall market, but this low valuation gives it more long-term upside than downside, in my opinion. We can't predict how its stock will perform in the near-term, but its 7% dividend yield (as of July 29) is a great incentive to keep investors patient.

If you're in on Pfizer for the long term, now seems like a good opportunity to begin a stake (or increase your current shares). But if you're looking to make some quick cash from a potential post-earnings swing, you're essentially gambling.